I've been somewhat reluctant to write about why the Democratic Party lost so badly, because it was an election where I don't know how they could've done better considering the state of the country and with all of the issues that President Obama was having to deal with and not looking good on really any of them other than perhaps Ebola. I think they could've used the President more, but more from behind the scenes and getting base Democrats to the polls and fundraising. Perhaps not using him with vulnerable Democrats in swing states and districts, but using him in those states perhaps at separate rallies to get Democrats to vote.
Now where I agree with Howard Dean is where he talks about message. The Republican Party didn't have one and really hasn't had one since 2004 when President Bush ran for reelection. Their campaign strategy was, "we know you don't like Obama, we probably dislike him more. Vote for us and we'll stop him. Oh by the way, the other guy voted with Obama 97% of the time". With Democrats saying "we disagree with the President on some things as well". But not explaining why the voted with the President so much and how those votes benefited their district or state.
What I think Democrats could've done was to say, "yeah the President and I agree on this and this is why and this is it benefits you Mr. and Mrs. taxpayer. And this is what I've done for you in Congress the last two or six years and how I've served you well. And oh by the, my opponent would've voted against you and your interests on all of these key issues like infrastructure, minimum wage health care, environmental protection. Which is why you should vote for me for reelection". That wouldn't of won back the House, but perhaps saved enough Senate seats to keep the Senate in Democratic control.